First, if it were added at the refinery or blender, it usually does not get well dispersed throughout each batch of fuel. Second, the effects of the product gradually dissipate within a few weeks and could be mostly gone by the time you fill your tank. For best results, it needs to be added to your tank just before you fill it up and your fuel needs to be used up within a few weeks for maximum benefit.

Question: How soon after using Diesel Fuel Synergizer+ will I notice improved performance.

Answer:

To get maximum benefit and performance, Diesel Fuel Synergizer+ must be used before you develop serious problems. Using it with every other fill up prevents problems from developing or getting worse. It will not repair damaged fuel systems or components that are near the failure point. Our testing has shown that performance improves in vehicles with mild symptoms or problems provided that there is no previously hidden damage.